Catalyst compositions and their use for chlorinating aromatic compounds

Abstract

A method for ring-halogenating an aromatic compound comprises contacting the aromatic compound with chlorine or bromine in the presence of a catalyst composition, where the catalyst composition comprises at least one salt comprising a metal selected from the group consisting of Group 13 metal; and a counterion derived from an acid having a pKa relative to water of 0 or greater; and at least one organic sulfur compound.

1. A method for ring-chlorinating toluene or o-xylene, which comprises contacting toluene or ortho-xylene with chlorine in the presence of a catalyst composition, wherein said catalyst composition comprises:
 at least one salt comprising a metal selected from the group consisting of indium and thallium; and a counterion derived from an acid, said acid having a pKa relative to water of 0 or greater; and 
 at least one organic sulfur compound selected from the group consisting of phenothiazine-N-carbonyl chloride, N-trifluoroacetylphenothiazine, 3-chloro-N-trifluoroacetylphenothiazine, and 3-trifluoromethyl-N-trifluoroacetylphenothiazine. 
 
     
     
       2. The method of  claim 1 , wherein said at least one salt is selected from the group consisting of indium telluride, thallium sulfide, indium sulfide, thallium oxalate, and indium oxalate. 
     
     
       3. The method of  claim 1 , wherein the catalyst composition comprises at least one reaction product of said at least one salt, and said at least one organic sulfur compound. 
     
     
       4. The method of  claim 1 , wherein said contacting takes place in the liquid phase. 
     
     
       5. A method for chlorinating toluene or ortho-xylene which comprises contacting toluene or ortho-xylene with chlorine in the presence of a catalyst composition prepared by combining at least one metal salt selected from the group consisting of indium sulfide, indium telluride, thallium sulfide, and thallium oxalate; at least one organic sulfur compound; and a chlorine atom source. 
     
     
       6. The method of  claim 5 , wherein said organic sulfur compound is selected from the group consisting of phenothiazine-N-carbonyl chloride, N-trifluoroacetylphenothiazine, 3-chloro-N-trifluoroacetylphenothiazine, and 3-trifluoromethyl-N-trifluoroacetylphenothiazine. 
     
     
       7. The method of  claim 5 , wherein said catalyst composition comprises at least one reaction product of said at least one metal salt, and said at least one organic sulfur compound. 
     
     
       8. The method of  claim 5 , wherein said contacting takes place in the liquid phase. 
     
     
       9. The method of  claim 5 , wherein said chlorine atom source comprises molecular chlorine or hydrogen chloride.